The Wambiana grazing trial : Key learnings for sustainable and profitable management in a variable environment

Abstract

Rainfall variability is a major challenge to sustainable and profitable beef production in northern Australia. While grazing management strategies to cope with this variability do exist, they have not been widely adopted. This is partly because there is little data on how these strategies perform relative to existing management.
A major problem is the perception that recommended strategies are not profitable and that managers need to stock relatively heavily to be financially viable.
The Wambiana trial was established in December 1997 near Charters Towers to objectively test how a range of grazing strategies cope with climate variability. To ensure relevance to the grazing industry, the trial was run in close association with a grazier advisory committee. Trial paddocks contained a range of soil types to reflect conditions in large, commercial paddocks.
The different grazing strategies tested were:
1. Heavy stocking (HSR) stocked at twice the long-term carrying capacity (LTCC) of the site.
2. Moderate stocking (MSR) stocked at the LTCC.
3. Variable stocking (VAR) with stocking rates adjusted annually in May based on forage availability.
4. Southern Oscillation Index (SOI)—variable strategy with stocking rates adjusted annually in November according to forage availability and the SOI.
5. Rotational wet season spelling (R/Spell) coupled with moderate-heavy stocking.